Low-temperature vapor synthesis of 1D β-Ga2O3 nanostructures on Si substrate by inert salt-assisted route

The attractive feature of one-dimensional inorganic nanomaterials grown on substrate at low temperature is the good adhesion between the deposited material and the substrate. In this work inert salt-assisted route has been extended to prepare Ga2O3 product on bare Si substrate. By using CaF2 powder as a dispersant, the vapor pressure of metallic Ga is increased greatly as compared to its non-dispersed state. This allows for the β-Ga2O3 nanostructures to be formed at a relatively low temperature of 650 °C as a result of direct oxidation of the well-mixed metallic Ga and CaF2 powder. This temperature is much lower than the synthetic temperature required in the cases of direct oxidation of metallic Ga as reported by others. The as-prepared Ga2O3 nanowires and nanobelts are characterized by XRD, SEM, EDX, TEM and PL. The vapor–solid growth process was also discussed for the as-prepared Ga2O3 product on Si substrate. The interesting results indicate the wide applications of inert salt-assisted route to vapor growth of other nanomaterials at relative low temperature.